Search results for "Memory."

Effects of an incremental maximal endurance exercise stress-induced cortisol on cognitive performance

2019

Exercise; Cognitive functions; Cortisol Ejercicio físico; Funciones cognitivas; Cortisol Exercici físic; Funcions cognitives; Cortisol Objectives: It can be hypothesized that cognitive performance decreases after fatigue protocol when it coincides with the maximum peak of cortisol. The first aim of this study was to elucidate the effects of a single bout of high intensity exercise on behavioural (i.e., attention and memory) and physiological (i.e., salivary cortisol) responses. The second objective was to evaluate the effect of the performance of the cognitive tasks on cortisol levels. Methods: Thirty-four physically active men (at least 5 days/week of physical activity practice) 38.11 (1.5…

IMPAIRED ALLOCENTRIC SPATIAL MEMORY UNDERLYNG TOPOGRAPHICAL DISORIENTATION

2006

The cognitive processes supporting spatial navigation are considered in the context of a patient (CF) with possible very early Alzheimer's disease who presents with topographical disorientation. Her verbal memory and her recognition memory for unknown buildings, landmarks and outdoor scenes was intact, although she showed an impairment in face processing. By contrast, her navigational ability, quantitatively assessed within a small virtual reality (VR) town, was significantly impaired. Interestingly, she showed a selective impairment in a VR object-location memory test whenever her viewpoint was shifted between presentation and test, but not when tested from the same viewpoint. We suggest t…

Immersive Versus Non-immersive Experience: Exploring the Feasibility of Memory Assessment Through 360° Technology

2019

Episodic memory is essential to effectively perform a number of daily activities, as it enables individuals to consciously recall experiences within their spatial and temporal environments. Virtual Reality (VR) serves as an efficacious instrument to assess cognitive functions like attention and memory. Previous studies have adopted computer-simulated VR to assess memory, which realized greater benefits compared to traditional procedures (paper and pencil). One of the most recent trends of immersive VR experiences is the 360° technology. In order to evaluate its capabilities, this study aims to compare memory performance through two tasks: immersive task and non-immersive task. These tasks d…

Acute effects of fluoxetine on inhibitory avoidance consolidation in male and female OF1 mice

2001

The effects of acute administration of fluoxetine on memory consolidation using an inhibitory avoidance task were investigated in male and female OF1 mice. Several doses of this antidepressant (5, 10, and 20 mg/kg) were intraperitoneally administered immediately after the training session. The test session was carried out four days later and response latencies were measured in both sessions. The results showed that the highest dose of fluoxetine significantly increased response latencies of inhibitory avoidance compared with the lowest dose and the control group. Sex differences in this task were observed, females showing a better performance. But the drug's effects were not sexually dimorp…

Acute stress and working memory in older people.

2015

Several studies have shown that acute stress affects working memory (WM) in young adults, but the effect in older people is understudied. As observed in other types of memory, older people may be less sensitive to acute effects of stress on WM. We performed two independent studies with healthy older men and women (from 55 to 77 years old) to investigate the effects of acute stress (Trier Social Stress Test; TSST) and cortisol on WM. In study 1 (n = 63), after the TSST women (but not men) improved their performance on Digit Span Forward (a measure of the memory span component of WM) but not on Digit Span Backward (a measure of both memory span and the executive component of WM). Furthermore,…

2016

The flexible access to information in working memory is crucial for adaptive behavior. It is assumed that this is realized by switching the focus of attention within working memory. Switching of attention is mirrored in the P3a component of the human event-related brain potential (ERP) and it has been argued that the processes reflected by the P3a are also relevant for selecting information within working memory. The aim of the present study was to further evaluate whether the P3a mirrors genuine switching of attention within working memory by applying an object switching task: Participants updated a memory list of four digits either by replacing one item with another digit or by processing…

Adaptive memory programing for the robust capacitated international sourcing problem

2008

The International Sourcing Problem consists of selecting a subset from an available set of potential suppliers internationally located. The selected suppliers must meet the demand for items from a set of plants, which are also located worldwide. Since the costs are affected by macroeconomic conditions in the countries where the supplier and the plant are located, the formulation considers the uncertainty associated with changes in these conditions. We formulate the robust capacitated international sourcing problem by means of a scenario-optimization approach. When dealing with uncertainty, one of the most common approaches in the literature is to formulate the problem via a set of possible …

Scatter Search and Path Relinking: Foundations and Advanced Designs

2004

Scatter Search and its generalized form Path Relinking, are evolutionary methods that have been successfully applied to hard optimization problems. Unlike genetic algorithms, they operate on a small set of solutions and employ diversification strategies of the form proposed in Tabu Search, which give precedence to strategic learning based on adaptive memory, with limited recourse to randomization. The fundamental concepts and principles were first proposed in the 1970s as an extension of formulations, dating back to the 1960s, for combining decision rules and problem constraints. (The constraint combination approaches, known as surrogate constraint methods, now independently provide an impo…

Auditory Event-Related Potentials in the Study of Developmental Language-Related Disorders

1997

This article reviews recent auditory event-related potential (ERP) studies of developmental language disorder (DLD) and dyslexia/reading disorder (RD). The possibility of using ERPs in searching for precursors of these disorders in the early development of infants at risk is also discussed. Differences in exogenous/sensory ERPs at the latency range of P1 and N1-P2 components have been reported between groups with DLD and RD and control groups. Latency differences between the groups may be related to a common timing deficit suggested by some researchers to be one of the possible underlying factors both in DLD and dyslexia. N1 amplitude group differences may be partly related to arousal/atten…

Facial emotion recognition in children and adolescents with specific learning disorder

2020

(1) Background: Some recent studies suggest that children and adolescents with different neurodevelopmental disorders perform worse in emotions recognition through facial expressions (ER) compared with typically developing peers. This impairment is also described in children with Specific Learning Disorders (SLD), compromising their scholastic achievement, social functioning, and quality of life. The purpose of our study is to evaluate ER skills in children and adolescents with SLD compared to a control group without learning disorders, and correlate them with intelligence and executive functions. (2) Materials and Methods: Our work is a cross-sectional observational study. Sixty-three chil…